Private by design
image processing stays in your browser. ResizeNest does not need your original image uploaded to an application server.
Image tool
Compress Images
Reduce image file size with format-aware settings while keeping dimensions by default. Processing runs locally on your device and final savings are measured from the actual output bytes.
Local processing Batch ready JPG · PNG · WEBP · AVIF
Start here
Use compress images now
No account is required. Choose a file and work directly in this browser.
Real output
Results come from the actual processing pipeline, with measured dimensions, bytes and format instead of placeholder estimates.
Simple workflow
Process one image or a local batch, then download current successful results.
Three simple steps
How to use compress images
- 01
Choose, drop or paste one or more JPG, PNG, WebP or AVIF images.
- 02
Start with direct Quality compression, choose Reduce by % for a measured byte-reduction target, or use Target size. PNG stays lossless unless you explicitly choose another output format.
- 03
Preview quality on a reduced non-export image, then process full resolution and download current results individually or as a ZIP.
Useful details
Built for a clear, predictable result
Understand what the tool does before you download the result.
Lossy and lossless compression
JPEG, PNG, WebP and AVIF can use quality-based compression. PNG quality reduces RGB color precision before normal PNG encoding and OxiPNG optimization while preserving alpha and dimensions; an explicit Lossless PNG option keeps pixel values exact. WebP can also switch explicitly to lossless mode. A quality number is not treated as equivalent across codecs.
Quality, percentage and measured target size
Quality is the default quick mode. Reduce by % converts the requested saving into a byte target for each source image, while Target size uses an explicit KB or MB limit. Target modes search measured encoded candidates within your quality and dimension limits and report target not-met instead of pretending they succeeded.
Why a file can get larger
Already optimized images may not shrink after a fresh encode, especially when metadata removal requires rewriting the file. ResizeNest shows negative savings honestly instead of hiding them.
Private local batch
The workflow runs through the shared browser worker. Mixed-format batches keep format-specific settings, preserve successful files when another fails, and ZIP only current successful outputs.
Questions, answered
Frequently asked questions
Does compression resize my images?
No by default. Dimensions stay unchanged. They can shrink only in Reduce by % or Target size mode when you explicitly allow dimension reduction.
Is JPEG quality 100 lossless?
No. JPEG remains a lossy codec at quality 100. ResizeNest does not label it lossless.
Why is there no PNG quality slider?
The baseline PNG path is lossless, so a lossy quality slider would be misleading. PNG target-size mode can report not-met when the byte limit cannot be reached under your constraints.
Does changing quality change the URL?
No. Preview, processing, editing and downloads remain on /compress-image.